Disable the ability to remotely shutdown the computer browser service.

Disable the Ability to Remotely Shutdown the Computer Browser Service -
It is possible for a malicious user to shut down a computer browser, or all
computer browsers, on the same subnet. If all of the computers on the same
subnet are shut down, they can then declare their own computer the new master
browser. Option affects the whole PC. Reboot your PC to activate or deactivate
this option. Applicable to Windows NT/2000/XP